This disclosure relates generally to computer system resource virtualization, and more particularly to hypervisor controlled redundancy for Input/Output (I/O) paths using virtualized I/O adapters.
Redundant physical I/O paths, where multiple physical paths exist from a computer to the storage devices, are commonly defined to provide high availability for applications executing on the computer. However a large computing environment, such as a cloud cluster of physical servers, may host several hundred virtual machines (VM) on the physical servers. To achieve I/O path redundancy in this virtual environment, traditionally may require at least two physical adapters for each VM, increasing both total cost of ownership and system administration complexity.
In an alternate solution, configuring Single Root I/O Virtualization (SRIOV) adapters in the computing environment provides the required path redundancy, through the multiple virtual functions (VF) available in each SRIOV adapter. While an improvement over multiple physical adapters, both physical adapters and SRIOV adapters require manual configuration to implement path redundancy. Manual configuration, being error prone, may lead to a single point of failure within the computing environment. Additionally, unless expertly configured and continually monitored with specialized performance management software, poor utilization of the adapter's bandwidth may result.